My turn for computer issues...

Have had two problems this week.
The first I fixed: My 4 1/2 year old Inspiron 6000 would have the screen go from regular to battery mode for no reason. Figured out the power supply was going bad and used another one.
The second popped up yesterday.
On the right side of the screen, an inch or so in and an inch or so wide, there's a vertical band running the depth of the screen. You can still see the screen and what's on it, it's just fainter.
I'm pretty sure it's not the video card; I took a screen shot to post here, copied it into as a photo and cropped it, and you can't see the light band. Just guessing, it's the LCD screen or the video cable. It hasn't changed in size or variance since it started doing it. Lookingat it through a lupe, it looks like half the nits just stopped working.
Question for the class is, if the cable was going bad would it just cut out all or part of the screen or would it fade? Or does it mean the screen is about to go?
The laptop has been good and other than adding more memory and xp crashing so hard (in the last two weeks of my warranty) I had Dell replace the hard drive, I haven't had a problem. I know it's probably as old as I am in computer years, bit now is not the time I can sink $1,000-1,300 into a new laptop either.
And if it is the screen, how tough is it to change on my own?

K, my guess is there is damage to the LCD screen. If the backlight on the LCD were going, you would get a reddish glow - especially when you turn it on, but not a line or stripe.

I've swapped out laptop screens - if you're replacing the screen only it can be a royal pain, especially if you don't know what you're doing. For the age your computer is, I would suggest either living with the stripe or find a new lid on eBay because installing the entire screen/lid assembly as one is much easier than taking the lid apart and installing a new LCD.